Conventionally, a technology has been proposed to improve the fuel efficiency of a vehicle by having the engine stop automatically while the vehicle is stopping or traveling (see, for example, Patent Documents 1-2).
Patent Document 1 discloses a start-stop control apparatus that has the engine stop automatically when the vehicle decelerates or stops (when the speed is reduced to a predetermined permission speed or lower).
Patent Document 2 discloses a vehicle control apparatus that has the engine stop automatically so that the vehicle travels by coasting (traveling by inertia) when a predetermined vehicle condition is satisfied while the vehicle is traveling (for example, the accelerator pedal is released while traveling at a predetermined speed or greater).
On the other hand, if the engine stops automatically as in Patent Documents 1-2, the headlight lighting in the night may go out or flicker due to a voltage drop of the battery when restarting the engine after it has stopped automatically. If the headlight lighting in the night goes out or flickers in this way, there may be unfavorable influences on the driver or other vehicles.
Thereupon, Patent Document 3 discloses an automatic stopping and starting apparatus that does not have the engine stop automatically while the headlight is on, to prevent the engine from stopping automatically in the night or in dark surroundings, and to prevent the headlight from going out.